Spabk-pi



UNITED, sTATEs PATENT oEEIoE.

y FRED BCHEOEDEB, QLEVSEIAND, OHIO.

.specification e: amm naar. Patented Dee. 2, 1,919.

SPARK-PLUG.

Application led November 1, 1917. Ierial Re. 159,868.

To all whom it may concern Be' it known that I, FEED Scnnonnnn, acitizen of the United States, and resident of Cleveland, in .the countyof Cuyahoga and State of Ohio, have invented certain new and usefulImprovements in Spark-Plugs, of which I hereby declare the following tobe full, clear, and exact description, such vas will 'enable othersskilled in the art to which". it appertains toV make and use same.

The objects of the invention are -to provide a novel form of spark pluin which a "heat as rapidly as solid metal but absorbsmore powerfulsparkcan be o tained and in, which the insulated core is" protected fromexcessive heat by means pf an inter.

and slowly to the porcelain. The metal gauze also has'a cushion elect toreduce the 1am upon the insulation and prevent it from cracking if itshould receive a sudden blow from any source. A peculiar formation ofsparking terminals is shown in the figures where a central electrodeterminates in acircular'orhook shaped extremity H which encircles ametal rod I secured transversely of the recess J inthe body of the plug.

The circular terminal produces at least two heavy sparks,one from thecorner L' and one from the point l( across the gap to the centralAterminal I. At other points suchas YV the terminals are closer togethermediate body of heat absorbing and dis-f and Va spark can be producedfrom a current tributing material whereby the core will escape irregularvexpansion and its life will be greatly prolonged.

The invention further comprises the com bination and arrangement of artsand construction of details hereinar described, shown ih the,accompanying drawings and specifically pointed out m the claims.

'In the accompanying drawings Figure 1 is a side elevation broken awaytn show the spark producing terminals.

is a plan of the lower end thereof. In these views A represents thebody'of the plug. B the porcelain or other body of insulation or core, Cthe central electrode, D the clamping sleeve for the porcelain core.E,'E, are lock nuts for the electrode.

The electrode C is spaced from the porcelain and the annularspacelpartiallyis filled with the inner lining F formed of `mica orother insulating and vitreous material, and between the mica andporcelain is shown a second layer 'G' composed of metal'gauze' or otherporous or spongy metalmica, and by distributing -it evenly to the innersurface ofthe porcelain Vrevente irre ilar expansion and contractionthereof, angl', cracking caused thereby.

The' metalgauze does -not conduct the and diffuses it and transmits itmore evenly Fig. 2 is a longitudinal central section thereof. Fig. 3v

of `low voltage. The point K of the circular terminal Vis turned upwardand hence prevents the accumulation of oil thereon and consequentdeposit of carbon to interfere with a clear spark.

Other advantages are that if one portion of either terminal becomesfouled, the other portions will not fail to produce a spark, at

one o1" more sion.

points, and cause the explo- The two layers F and G' terminate above thelower end of the porcelain an'd thus are I.' protected 'from 'the directheat of the explois entirely o 'n1 at the l'ower end and hence Iwitliits wa ls and the terminals Hand I can readily be cleansed if theyshould become coated @with carbon.

Having .described thc invention what I claim as new and desire toseclreby Letters Patent is:

'1. In a sparkplug, a metal body, a central electrode, an inneliningtherefor, an

outer insulation andan intermediatelayerof ,cushioning and heatdiffusing material, substantially as rlescribeth Q. In a spark plug, ametal body, a cent-l'nl electrode, un inner insulatingr liningsnlations, and means for securing said parts therefor, un outerinsulation, und n layer of together. 10 spongy metallic substanceinterposed be- In testimony whereof, I hereunto 'sot my tween said outernml inner insulntions. hund this 24th day of October, 1917.

3. In n spark plug. :t metal body` n cen- FRED SCHROEDER. trailelectrode. an inner insulation therefor. In presence of an outerinsulation, a layer of spongy metal- S. W. SANGSTER,

liv suhstnnrn -intei'posed-ibetween said in- WM.:M. MONROE.

